Patent Application
20190241847
The present invention relates to algae growth systems and in particular to a Symbiotic Algae System.
Mass cultivation of algae has been used for creating nutritional supplements, fertilizer, and food additives. Commercial growth of algae has also been explored to create biologically-derived energy products such as biodiesel, bioethanol, and hydrogen gas. As a biofuel feedstock, algae provide multiple environmental benefits and present significant advantages over traditional plants/crops used for biofuel production (e.g., corn, sugarcane, switch-grass, etc.). For example, unlike traditional food crops that are being used to produce biofuels (e.g., corn, sugarcane, etc.), algae does not compete with food and water resources; it grows significantly faster than traditional crops used for biodiesel; algae produce up to 300 times more oil than traditional crops on an area basis; algae fuel has properties (low temperature and high energy density) that make it suitable as jet fuel; and algae can be produced so as to provide a nearly continuous supply of fuel. Moreover, algae can treat industrial, municipal, and agricultural wastewaters, capture carbon-dioxide, and provide valuable byproducts, such as, but not limited to, protein-rich feed for farm animals, organic fertilizer, and feedstock for producing biogas.
Algal biomass can accumulate up to 50% carbon by dry weight, therefore producing 100 tons of algal biomass fixes roughly 183 tons of CO2—providing a tremendous potential to capture CO2 emissions from power plant flue gases and other fixed sources. Ideally, biodiesel from algae can be carbon neutral, because all the power needed for producing and processing the algae could potentially come from algal biodiesel and from methane produced by anaerobic digestion of the biomass residue left behind after the oil has been extracted.
The successful role of algae in wastewater treatment has been documented since the early 1950s, and algal wastewater treatment systems are known to utilize the extra nutrients including nitrogen, phosphorus, potassium, heavy metals, and other organic compounds from wastewater. For example, an algal turf scrubber system feeding algae a diet of dairy manure can recover over 95% of the nitrogen and phosphorus in the manure wastewater. Additionally, lipid/oil productivity occurs in algal wastewater treatment systems, but there are few, if any, known robust algae strain(s) for oil production that use wastewater as a primary feedstock. For example, a polyculture (dominated by Rhizoclonium sp.) used in algal turf systems for treating dairy and swine wastewater had very low lipids/oil content (fatty acids contents of 0.6% to 1.5% of dry algae weight) and other researchers have reported 2.8 g/m2 per day of lipid productivity from algal polyculture combined with dairy wastewater treatment.
Algae's other byproducts can also be beneficial. For example, the value of algae as food was explored as early as 1950s, and some have demonstrated the concept by raising baby chickens to adults on twenty percent (20%) algae fortified feed (grown on pasteurized chicken manure). The antibiotic Chlorellin extracted from Chlorella during World War II marked the start of an algae based pharmaceutical and nutraceutical industry that led to the Japanese Chlorella production facilities during 1960s, further leading to current production of Chlorella, Spirulina, Dunaliella and Hematococus on a commercial scale. Fertilizers from algae have also shown equivalence to commercial organic fertilizers in terms of plant mass and nutrient content.
Despite all of the aforementioned benefits, algae biomass production and the production of algal oil (i.e., biofuels from algae) are primarily hampered by the high cost of producing algae biomass (currently either requiring large amounts of land/water and/or large sterile facilities). There have been attempts to offset this high cost by using the various traits of algae to their greatest benefit. For example, biofuel production from algae has been combined with wastewater treatment (as discussed above) and has been shown to be 40% more cost effective than the best conventional alternatives, but still has not been economically viable due to low lipid production. As another example, entities have attempted to vary the type of cultures used—for example, algae monoculture (requiring sterile conditions) versus polyculture-based wastewater treatment. However, the results of these trials have not proven themselves. Other disadvantages of current algae biomass production include, but are not limited to, the availability of low-cost throughput sugar feed-stocks for growing algae, treating effluent created during production, and the requirement of nitrogen and phosphorus supplements. Until such time as these algae production related issues are solved, production of oil feedstock from algae is likely to remain commercially infeasible.
For this reason, the system and process disclosed herein addresses the challenges involved in materializing cost-efficient algae based on a robust, easily adaptable, environmentally friendly system that is capable of growing algae biomass on a commercial scale for biofuel, fertilizer, animal feed, and other byproducts. The symbiotic algae system and process disclosed herein also holds great potential for industries, farms and municipalities, especially dairy farms and breweries, because the system allows these entities to more efficiently and effectively meet government standards for handling and recycling of wastes.
In an exemplary aspect, a symbiotic algae system comprises a first algal growth component, wherein the first algal growth component includes a heterotrophic organism, and wherein the first algal growth component produces a first effluent and an off-gas; and a second algal growth component is fluidly coupled to the first algal growth component, and the second algal growth component including at least one organism from the group of: a photoautotrophic organism, a mixotrophic organism, and a heterotrophic organism, and wherein the second algal growth component receives, as an input, the first effluent and the off-gas and produces a second effluent.
In another exemplary aspect, a symbiotic algae system comprises a first algal growth component, wherein the first algal growth component includes a heterotrophic organism, and wherein the first algal growth component produces an first effluent and an off-gas; and a second algal growth component fluidly coupled to the first algal growth component, wherein the second algal growth component includes at least one organism from the group of: a photoautotrophic organism, a mixotrophic organism, and a heterotrophic organism, and wherein the second algal growth component receives, as a first input, the first effluent and the first off-gas and produces an second effluent and a second off-gas; and wherein the second effluent and the second off-gas are received as inputs to the first algal growth component.
In yet another exemplary aspect, a symbiotic algae system comprises a waste nutrient preparation sub-system; an algal culturing system including: a first algal growth component fluidly coupled to the waste-nutrient preparation sub-system, wherein the first algal growth component includes a heterotrophic organism, and wherein the first algal growth component produces a first effluent and an off-gas; and a second algal growth component, wherein the second algal growth component includes at least one organism from the group of: a photoautotrophic organism, a mixotrophic organism, and a heterotrophic organism, and wherein the second algal growth component receives, as an input, the effluent and the off-gas and produces a second effluent; and an algal harvesting system fluidly coupled to the algal culturing system; an algal biomass processing system fluidly coupled to the algal harvesting system; and a byproducts system fluidly coupled to the algal biomass processing system.
For the purpose of illustrating the invention, the drawings show aspects of one or more embodiments of the invention. However, it should be understood that the present invention is not limited to the precise arrangements and instrumentalities shown in the drawings, wherein:
A symbiotic algae system according to the present disclosure provides a cost-efficient means of producing algae biomass for many applications, such as, but not limited to, feedstock for biofuel manufacture which desirably impacts alternative/renewable energy production, nutrient recovery from waste streams, and valued byproducts production (nutraceuticals, pharmaceuticals, animal feed, etc.). A symbiotic algae system as discussed herein is an integrated systems approach to wastewater treatment, algal strains selection for oil production, CO2 capture or nutrient capture from heterotrophic processes, and recycle of algal-oil extraction waste as feedstock for biogas production. Embodiments of a symbiotic algae system as discussed herein present an economically viable algae production system and process that allows algae-derived biofuels to compete with petroleum products in the marketplace.
A symbiotic algae system as discussed herein is, at a high level, a scalable process for cultivating algae biomass, in which a heterotrophic (i.e., non-light dependent) algal growth strain is used to provide carbon dioxide and/or effluent to a photoautotrophic or mixotrophic or a combination of the three cultivation processes (i.e., photoautotrophic, mixotrophic, and heterotrophic) while concomitantly producing algae biomass or lipids for biofuel production. In certain embodiments, the photoautotrophic or mixotrophic or heterotrophic cultivation portion of the symbiotic algae system may result in the cultivation of additional algae biomass, but could include (alternatively or additionally) the cultivation of any photoautotrophically or mixotrophically grown microbial plant matter that requires carbon dioxide and/or effluent containing nutrients, such as nitrogen, phosphorus, and organic carbon. As will be discussed in more detail below, the symbiotic algae system can efficiently use nutrients from both commercial and/or other waste streams for the production of lipids for use with biofuels, and as such, the energy return on investment scenarios are significantly higher than previously considered possible. This symbiotic algae system provides a robust scalable option which has improved cost efficiencies due to production of additional desirable byproducts such as fertilizer.
Turning now to the figures, and specifically with reference to
Waste nutrient preparation sub-system 104 is generally configured to treat incoming feedstocks (e.g., manure, municipal waste) for the rest of SAS 100. The design and configuration of waste nutrient preparation sub-system 104 depends on the desired inputs for SAS 100. As shown in
In an exemplary embodiment, waste nutrient preparation sub-system 104 is a manure settling and solids preparation unit that outputs liquid manure waste to algal culturing system 108. In this embodiment, manure is combined with water run-off (e.g., fresh water input 128) and collected in a large separation tank (e.g., separator 136). The denser solids are allowed to sink to the bottom (or in certain embodiments are mechanically separated) and the output liquid manure water is pumped from the tank. In an exemplary embodiment, solid wastes, for example, ligno-cellulosic material such as grain spoilage or grasses, is pretreated in solids treatment unit 140 with or without manure effluent to prepare the nutrients (e.g., different forms of nitrogen or phosphorus or sugars or organic carbon) for algal culturing in algal culturing system 108.
Algal culturing system 108 is generally configured to grow algal biomass from numerous nutrient and/or waste streams. In an exemplary embodiment, algal culturing system includes an algal core 156 (
As discussed in more detail below, the design of algal core 156 determines the amount of algae produced in AGC 152B based on the amount of CO2 produced by AGC 152A or vice versa with oxygen production by AGC 152A fed to AGC 152B. For example, if AGC 152A produces about 1.8 tons of CO2, one would expect that up to about 1 ton of dry algae biomass would be produced by AGC 152B.
AGC 152A has the advantage of accepting a myriad of inputs. For example, and as described previously, AGC 152A can use liquid manure waste as in input, or can use organic carbon from commercially available clean sources (e.g. sugars) or other waste streams, such as, but not limited to, grains spoilage from farms, brewery waste, liquids containing sugars from food waste, industrial wastes, farm operation wastes, or a mixture of different wastes. Algal biomass production at AGC 152A can be maximized by using the naturally occurring or genetically enhanced algae strains, monoculture or polyculture, and/or other microbial strains such as bacteria and/or fungi that is best suited for the feedstock (e.g. sugars available from market or from waste sources) available at the target location. In other words, certain algae do better with certain carbon inputs than others and the determination of which algal strain should/can be used may be based on a number of factors, including, but not limited to, the input stream, desired output (e.g., a certain reduction in a certain component of the input steam or to maximize the growth of biomass), expected temperature, and pH. In an exemplary embodiment, the algae, Chlorella vulgaris, has been successfully cultured in dairy manure effluents. In another embodiment, AGC 152A can use and produce non-algae strains, such as the fungal strain, Trichoderma reesei, for converting aforementioned throughput feedstock into byproducts.
In an exemplary embodiment, AGC 152A includes heterotrophic algae, which is known to produce dense algae growth and a relatively high amount of useful byproducts. Heterotrophic algae can be grown in containers such as fermenter(s), or closed or open system(s), or a combination or a hybrid form of the aforementioned. Standalone growth of heterotrophic algae is scalable in large sized vessels (such as, but not limited to, fermenters), and under heterotrophic growth conditions, respiration rates equal or exceed the theoretical minimum cost of biomass synthesis and biomass synthesis can achieve nearly the maximal theoretical efficiency.
One of the outputs (in addition to generated algal biomass for lipid extraction) of AGC 152A is an off-gas, CO2, which is generated as a result of algae respiration due to organic uptake of carbon. The CO2 generated by AGC 152A is used as an input for AGC 152B.
AGC 152B is designed to accept the output of AGC 152A (which are typically byproducts of AGC 152A, such as, but not limited to, suspended solids, inorganic carbon, organic carbon, phosphorus, potassium, nitrogen (in various forms including ammonium, nitrate nitrogen, and suspended nitrogen)). As such, AGC 152B can be a photoautotrophic, a mixotrophic, or a combination of both photoautotrophic and mixotrophic production systems of algae fed by the CO2 produced by AGC 152A. AGC 152B can take the form of open, closed, or hybrid systems of algae growth and therefore can be implemented by various methodologies, such as, but not limited to, a tank, a bag, a fermenter, a tubular vessel, a plate, and a raceway, of any shape, size, or volume. Typically, AGC 152A and 152B are in separate containers or growing areas as it facilitates the independent growth of each algae in each AGC.
In an exemplary embodiment, AGC 152B uses clean sources of additional nutrients or captures nutrients from waste or wastewater streams, for example, but not limited to, anaerobically or aerobically digested effluent from dairy farms, industrial operations such as breweries, food waste, municipal waste, etc. The CO2 input stream from various industrial operations, such as flue gases, supplied to second algal growth component 312 may contain other nutrients that promote algae biomass growth. While AGC 152B has been previously described as one or more of a photoautotrophic, mixotrophic, and heterotrophic algal growth, it could also include the cultivation of any biomass that requires the addition of inorganic carbon (CO2) and/or organic carbon and/or nutrients (such as nitrogen and phosphorus and other micro or macro nutrients) for its growth.
In order to size algal core 156 (and ultimately determine an estimate of the total expected biomass (TEB) production of the system), the amount of algal biomass producible from AGC 152A at the site is determined based on the amount and type of throughput feedstock available, e.g., the amount available from on-site sources, brought from off-site sources, or combination of the two, to grow the respective algae type used in AGC 152A. For example, if the feedstock is nitrogen rich, algal types that may be paired with this feedstock include Chlorella vulgaris, Chlamydomonas reinhardtii, and Scenedesmus abundans. Alternatively, if the feedstock is phosphate rich, the algal types that may be paired with this feedstock include the bacteria Acinetobacter calcoaceticus or Acinetobacter johnsonii. Based upon the expected algal biomass producible from AGC 152A, an amount of CO2 available to AGC 152B from AGC 152A can be determined. The available CO2 and the amount of feedstock available to AGC 152B is determinative of the amount of biomass producible of AGC 152B. The TEB can then be determined as the sum of the algal biomass produced at AGC 152A and the biomass produced at AGC 152B.
The amount of biomass producible by either growth component, i.e., AGC 152A and AGC 152B, will be heavily influenced by the specific algae chosen for each respective component, and in the case of AGC 152B, the type of algae chosen. For example, a mixotrophic algal growth system requires less CO2 because it requires greater organic carbon uptake when compared to a phototrophic system. The type of algal system chosen for AGC 152B (and the specific algae) can be used to determine the size or volume required for AGC 152B when implemented in the form of, for example, a closed photobioreactor, an open tank, a raceway, or a pond system. For example, if an output of 1000 tons of Chlorella vulgaris grown in AGC 152B (e.g. a photobioreactor), that system would need at least 1800 tons CO2 as an off-gas input. To produce that much CO2, AGC 152A would need to be sized to grow enough heterotrophic biomass. In contrast, in the case of mixotrophic algal production, the CO2 requirement could be about 10 times lower.
A non-limiting example of the setup of algal culturing system 108 and the selection process for the algal strains used therein is now presented. In this example, the effluent or input into AGC 152 is brewery waste. This waste has a composition as follows:
Suspended solids (TSS) (mg/L) 318.00
Total C of TSS % dry wt. 18.50
Total N mg/L 14.74
NH4-N mg/L mg/L 0.05
Ortho-Phosphate mg/L 21.20Total P mg/L 23.60
K mg/L 53.90
Ca mg/L 33.40
Mg mg/L 10.30
Na mg/L 202
Fe mg/L 0.60
Zn mg/L 0.11
S mg/L 43.6
Based on literature and market research, and followed up by small scale experimentation, the strain Chlorella was chosen for AGC 152A due to its ability to use high amounts organic carbon (20% of dry weight of suspended solids is in the input stream) and because it also requires some nitrogen (N), phosphorus (P), and potassium (K) to grow. Chlorella also does not produce any toxic byproducts during growth that would need to be considered when selecting the algal strain for AGC 152B. Thus, given the composition of the input stream and the growth characteristics of Chlorella, it was selected to grow in a heterotrophic environment. The conditions for growing Chlorella included a temperature range of 28-32° C. and pH 6.5-7—these conditions were monitored using known techniques and adjustments to temperature and pH were made as necessary to support the algae's growth. Additional considerations for the heterotrophic system can include, but are not limited to, the oxygen level, the dissolved CO2 level, and the concentration of solids, each of which would impact growth rates, but not necessarily impact the choice of algae strain. It should be noted that other strains would also be suitable for growth with this input stream in a heterotrophic environment and a different strain may be chosen depending on whether the output from the second algal growth system is added as an input to the first algal growth system (and thus adding additional materials). In some embodiments, a systems solution may be necessary (e.g., an iterative analysis that evaluates a system as a whole to understand the impact of an alteration to one component of the system). Other suitable strains may be, but are not limited to, Haematococcus pluvialis, Crypthecodinium cohnii, Neochloris oleoabundans, Schyzochytrium limacinum, Scenedesmus sp., Scenedesmus obliquus, Chlorella minutissima, Chlorella protothecoides, Chlamydomonas reinhardtii, Nitzschia laevis, Phaeodactylum tricornutum, Aurantiochytrium limacinum, Chlorella zofingiensis, Chlorella pyrenoidosa, Chlorella sp., Chlorella saccharophila, Chlorella sorokiniana, Galdieria sulphuraria, Dunaliella sp., Euglena gracilis, Nannochloropsis oculata, Nitzschia alba, Prototheca zopfii, Scenedesmus acutus, Schizochytrium sp., Schizochytrium sp., Brachiomonas submarina, Dunaliella tertiolecta, Tetraselmis verrucosa, Tetraselmis suecica, Tetraselmis tetrathele, Poterioochromonas malhamensis, Dunaliella salina, and Chlorella regularis.
After growing the Chlorella, the resulting biomass is harvested from AGC 152A. The remaining effluent contains less organic carbon and suspended solids than in the original brewery waste input stream, which allows light penetration in the effluent. Since a heterotrophic algal strain such as Chlorella, when grown heterotrophically, is less efficient in utilizing nitrogen and phosphorus, a majority of the nitrogen and phosphorus in the input stream to AGC 152A remains along with several micro-nutrients such as Ca, Mg, Na, Fe, Zn S, etc. Thus, in this experiment, the second effluent (resulting from the first system after separating biomass) composition is as follows:
Suspended solids (TSS) mg/L 47.95
Total C of TSS % dry wt. 1.66
Total N mg/L 10.3
NH4-N mg/L 0.03
Orth-phosphate mg/L 14.9Total P mg/L 16.1
K mg/L 53.6Ca mg/L 16.6
Mg mg/L 7.96
Na mg/L 175
Fe mg/L 0.16
Zn mg/L 0.04
S mg/L 32.00
As is notable, there is less organic carbon left in this effluent, which is to be expected based upon the selection of Chlorella in AGC 152A, and a significant amount of nitrogen and phosphorus also remain. Accordingly, the algal strain for AGC 152B was chosen so as to be able to capitalize on availability of non-organic carbon from CO2 gas (an off-gas of AGC 152A), and the ammonium, nitrogen, and phosphorus in the effluent coming from AGC 152A. For this experiment, the algal strain Scenedesmus was chosen, which requires inorganic carbon (CO2) to grow and does a better job at removing nitrogen and ammonium than does the heterotrophic Chlorella. For the phototrophic system, additional considerations for system design include, but are not limited to, CO2 level, the concentration of solids, light penetration, and the depth of growth system. Other suitable phototrophic strains could be Botryococcus braunii, Chlorella sp., C. minutissima, C. vulgaris, C. pyrenoidosa, Spirulina sp., Dunaliella sp., Hematococus sp., Schizochytrium sp., Nitzschia sp., N. dissipata, N. palea, Boekelovia hooglandii, Monallantus salina, Navicula sp., S. rophila, N. acceptata, N. pelliculosa, N. pseudotenelloides, Dunaliella Sp., Neochloris oleoabundans, Monoraphidium sp., Amphora Ourococcus, Nannochloris sp., Nannochloropsis salina, Scenedesmus sp., Scenedesmus obliquus, Scenedesmus quadricauda, Scenedesmus caudata, Scenedesmus bijunga, Desmodesmus sp., Ankitodesmus Chaetoceros sp., C. calcitrans, C. muelleri, Cyclotella cryptica, Amphiprora hyalina, Cylindrotheca sp., Pavlova lutheri, Amphora, E. oleoabundans, A. falcatus, C. sorokiniana T suecica, Lygnbya sp., Spirogyra sp., Ulothrix sp., Microspora sp., Claophora sp., Melosira sp., Lygnbya sp., Aphanocapsa sp., Asterionella sp., Navicula sp., Stephanodiscus sp., Tabellaria sp., Micractinium sp., Actinastrum sp., Rhizoclonium hieroglyphicum, Microspora willeana L, Ulothrix ozonata Kütz, Rhizoclonium hieroglyphicum Kütz, Oedogonium sp., Euglena sp., Chlamydomonas sp., Oscillatoria sp., etc. Although certain strains listed above for the second algal growth component are also listed from the first algal growth component, it is understood that the same strain would not be used for both the first and second algal growth components.
At a high level, the algal selection process is focused on the inputs to the given algal growth component, e.g., AGC 152A. Once the inputs are known (generally through laboratory analysis), the algal strain that provides the desired outcome, e.g., biomass production, removal of an entrained element, contamination reduction, etc., is chosen. As is understood by a person of ordinary skill in the art, suitable algal strains may be found (or made) from published research and databases, bioprospecting, or genetic engineering. Generally, a small-scale pilot is conducted prior to full system implementation to confirm the algal strain growth rates, its ability to meet outcome expectations, to determine the byproducts after growth, and to determine the existence (or lack thereof) of unexpected outputs, e.g., growth inhibiting compounds, that may need to be removed or destroyed (via, for example, heating up the effluent) before feeding the output to, for example, AGC 152B. Notably, even if the selected algal strain produces a toxin or growth inhibiting compound, an algal strain can be selected that will grow in the presence of that compound or toxin. See Harris, D. O., Growth Inhibitors Produced by the Green Algae (Volvoaceae), Arch Mikrobiol 76, 47-50 (1971). In any event, it would be understood by a person of ordinary skill in the art that a number of suitable algae strains would be available for pairing with a given input which would result in algal strain growth and would produce an output that would be pairable with another algal strain.
The algal system described herein may include a detector (or multiple detectors) to detect and provide information regarding the growing conditions in AGC 152A and 152B, and may further include one or more controllers to automatically shut down or start-up operation of AGC 152A and 152B in response to the information provided by the detector. Parameters (growing conditions) that may be monitored include, but are not limited to, the amount of light, the temperature, pH, and the presence (or absence) of contamination.
The algal system may include one or more detectors (sensors) and/or controllers which sense conditions in AGC 152A and/or 152B and alert a user to conditions that are favorable or unfavorable for growth. For example, the phototrophic reactor may be equipped with a sensor that measures or senses the quantity or amount of sunlight or other light (e.g. in lumens) that impinges on the phototrophic culture at any given time, or the cumulative amount of sunlight that impinges on the phototrophic culture during a period of time of interest (e.g. during a minute, and hour, a day, etc.). Detectors included with the algal system may be designed so as to provide information to a user whereby a user can decide whether to continue phototrophic culture, or to discontinue (stop, cease, shut down) phototrophic culture and harvest the resulting biomass. Although a heterotrophic bioreactor does not utilize sunlight, it may be situated in a manner that allows a sensor of relevant conditions to be associated therewith such as dissolved oxygen, pH, temperature, etc., and to record information and provide information that can be used to adjust conditions in the bioreactor to improve growing conditions.
In addition to sensing light levels, or instead of sensing light, the detector may be designed to also monitor (track, sense, measure, etc.) other parameters, including but not limited to temperature, the presence of contaminants, or in response to conditions in one or both of the reactors (e.g. when the heterotrophic reactor is inoperable due to maintenance, malfunction, etc.). Those of ordinary skill in the art will recognize that many useful parameters may be monitored, all of which are encompassed by the invention. Further, such detectors and controllers may be used to fine-tune the reactors, e.g. to detect and inform a user of the status (e.g. of growth rate) in the heterotrophic reactor so as to “ramp up” (or down) the level of activity in the phototrophic reactor, or vice versa, and may control feed rates of any inputs to one or both of AGC 152A and AGC 152B. For example, CO2 delivery to AGC 152B may be monitored so as to determine whether enough CO2 is coming from AGC 152A or if supplemental CO2 is needed (which can, for example, be provided by other facility operations, such as the exhaust from a combustible heating system). In other words, modulation of the activity of the two reactors in response to sensors need not be all or nothing, but can be implemented by degrees, either manually or automatically. In fact, when multiple reactors are employed, the controllers may be equipped to determine how many of the reactors are operable at a given time.
In another embodiment the size of algal core 156 can be deduced inversely, e.g., first the maximum amount of biomass producible via AGC 152B on the site is determined (usually space/volume limited) based upon the type of algal system, inputs, and space/footprint available, then the CO2 the requirements of the AGC 152B are determined, which can then be used to determine the composition and size of AGC 152A.
In yet another exemplary embodiment of algal core 156, an oxygen rich air supply from AGC 152A (when implemented as a photobioreactor as a result of photosynthesis by photoautotrophic or mixotrophic algae) is fed into AGC 152B (when implemented as a heterotrophic reactor to support growth of heterotrophic algae). This arrangement solves a major well-known constraint in closed photobioreactor systems caused by excessive oxygen production which has an adverse effect on the algae growth inside the photobioreactor.
In a further embodiment, an AGC 152A feeds AGC 152B while AGC 152B feeds AGC 152. For example, AGC 152A may feed CO2 to AGC 152B, while AGC 152B, concomitantly, feeds O2 to AGC 152B. Additional CO2 or O2 can be fed to the respective components for additional biomass production and carbon capture as desired.
Of the many advantages offered by SAS 100 and specifically by algal core 156, is the scalable nature of the system. Scalability is enhanced because heterotrophic algae (i.e., AGC 152A) is capable of dense growth when compared to photoautotrophic algae and certain mixotrophic algae. While density allows for greater biomass production per volume, heterotrophic algal growth in AGC 152A produces an off-gas, CO2 and effluent containing nitrogen, phosphorus, and other components requiring treatment before discharge. However, the need and concomitant expense of treatment can be mitigated (or even eliminated in certain embodiments) by incorporating AGC 152B because the second algal growth component uses the CO2 and effluent created by the AGC 152A, thus significantly reducing waste treatment costs while producing additional algal biomass.
While algal core 156 has been described above as a part of a larger system, e.g., SAS 100, algal culturing system 108, etc., it can also be implemented as a standalone system.
As shown in FIG.3, an algal core 200 can also use post algal harvest liquid effluent obtained from AGC 204A as an input for AGC 204B so as to provide an additional supply of nutrients.
In yet another embodiment of algal core 300, and as shown in
Another embodiment of algal core, algal core 300, is shown in
Returning now to a discussion of
When algal harvesting system 112 is in use, algae biomass from AGC 152A is provided to solid separator 160A, which in this embodiment is a settling tank that allows the algae mass to settle to the bottom of the tank. In this embodiment, the bottom quarter of the settling tank (or so) is then physically separated from the rest of the settling tank's contents. The top three quarters of the settling tank (generally a liquid layer) is pumped out of solid separator 160A (and can be re-fed into either AGC 152A or AGC 152B, or sent to algal biomass processing system 116, as discussed below) leaving only the bottom algae concentrate which can be subsequently removed.
Algal solids (also referred to as concentrate) separated out by algal harvesting system 112 are sent to algal biomass processing system 116, which can be a standalone unit or a combination of centrifugation, filtration, drying, gravity settling, microbial or chemical based biomass aggregation, flocculation and sedimentation, etc., to further concentrate the algal solids. As shown in
In another embodiment, algal biomass processing system 116 is implemented as a solid separator that includes a centrifuge and a filtration system (e.g., filtration 170, shown in
A non-limiting example of an example of an algal biomass processing system 116 including a filtration system is now presented. As algae is known to utilize from over 50% to 99% of phosphorus, the inclusion of a filtration system increases the removal of phosphorus from the effluent stream and produces a useful byproduct. In this example, manure waste was sent used in the symbiotic algae system, e.g., SAS 100. After growth of the algae in AGCs 152A and 152B, the resulting algal biomass was separated with a centrifuge. Analysis of the resulting effluent determined that the algae had removed 95.45% of the phosphorus and 98.99% of phosphate from the manure waste. The resulting effluent was then provided to one of three different filtration systems. Filtration system No. 1 consisted of ash material, which resulted in 99.93% of the phosphorus being removed and about 100% of the phosphate. Filtration system No. 2 consisted of biochar made from wood, which also resulted in 99.93% of phosphorus being removed and about 100% of phosphate. Filtration system No. 3 comprised a layered system including biochar, ash, and sand. This system resulted in the removal of between about 99.94% to 99.99% of phosphorus and about 100% of phosphate. The resulting liquid from each of the filtration systems discussed above had reduced dissolved organic material, and the carbon-based material (e.g. ash, biochar) after filtration was activated. Advantageously, the resulting carbon-based material can be included with other materials to create a soil amendment and/or fertilizer. In certain embodiments, the resulting carbon-based materials is added to the algae cake.
Although the filtration system described above is included with algal biomass processing system 116, the filtration system can be included in other stages of SAS 100 as well. For example, the filtration system can be included with waste nutrient preparation sub-system 104 as an effluent pretreatment unit that outputs liquid waste, with less total phosphorus and phosphates to algal culturing system 108. In an embodiment, separator 136 includes the filtration system. In another embodiment, the filtration system is included with algal culturing system or algal harvesting system 112, whereby the algae growth container or the settling tank, respectively, includes the filtration system.
Algae cake with or without the addition of wild or naturally occurring algae or the carbon-based materials from the filtration system can be dried or mixed with additional biomass for conversion into byproducts such as, but not limited to, fertilizers and biofuels. In some of the instances of biomass processing system 116, the algae cake is densified by the addition of a secondary material or a mix of materials such as sawdust, hay, grasses, pelletization or pucks waste or surplus, lumber waste or surplus, wood waste, or surplus, etc. These densification processes may be beneficial to the renewable diesel production processes described below, to the formation of a storable form of fertilizer, or for the creation of combustible algal pellets for burning in gasifiers for heat. In some instances, algae cake alone or mixed with one or several materials, as described above, is pelletized or prepared into pucks, briquettes, pellets, etc., thereby providing increased storability. In another embodiment, algae cake is mixed with grasses grown on wasteland, or in buffer zones for capturing nutrients, e.g., miscanthus, switchgrass, etc., and/or with the carbon-based materials from the filtration system and then is formed into pellets, briquettes, pucks, etc.
Byproducts system 120 further treats the outputs received from algal biomass processing system 116. In an exemplary embodiment, from the lipid layer, crude algae oil is extracted with a solvent and a catalyst through a suitable process (chemical or non-chemical) at biofuel processor 172 so as to produce biodiesel and glycerol. In another exemplary embodiment, algae cake is converted into different forms of marketable fertilizer (either or both liquid and solid types). The solid fertilizer can be made into different forms such as powder, granular, pelleted, etc. and can include different proportions of nitrogen, phosphorus, and potassium (commonly combined and referred to as N—P—K). Producing algae fertilizer with marketable N—P—K concentrations has proved elusive. However, in certain embodiments of SAS 100, different algae types (monocultures, polycultures, or aggregations of naturally occurring algae with or without other microbes or components), capable of capturing different fertilizer constituents (e.g., N, P, K), are grown separately either in the looped reactor or in combined or standalone autotrophic, mixotrophic, or heterotrophic reactors or open ponds. Harvested algae can then be mixed in different proportions to obtain the marketable equivalent compositions of N—P—K, for example, as in Alfalfa meal (N—P—K: 2-1-2); Soymeal (7-2-1); and chicken manure (1.1-0.8-0.5). Algae fertilizer can also be enhanced by blends of different commercially or locally available materials, for example, by adding trace minerals for creating algae-based seed starting mixes, or by adding potassium for creating certain desirable N—P—K composition. Granular fertilizer can be made using fertilizer processor 176, which, in an exemplary embodiment is a commercially available granulating machine. In an exemplary embodiment, algal cake with sufficient moisture is dried prior to granulation. It has been reported that solid form of fertilizer applications improves crop growth by providing the captured nutrients in a relatively stable and storable form, which is not possible with the application of liquid manure on the land via manure spreader. This inefficiency exists because there are only few time windows available for liquid manure spreading during the crop growth. However, using a storable, granulated form of algal-based fertilizer provides flexibility of application during the times when a manure spreader cannot be used, such as for dressing the corn plants at the appropriate stage of their development. An environmental benefit, among others, of removal of nutrients via algal fertilizer is the reduction of nutrient runoff into natural water bodies. Moreover, cost offsets would be economically beneficial as fertilizer production produces an income stream for the farms or other businesses.
In yet another embodiment of byproducts system 120, biofuel processor 172 can convert algal biomass directly from algal culturing system 108, or through algal harvesting system 112, or algal biomass processing system 116 into “renewable diesel” and byproducts via hydrogenation (treatment with addition of hydrogen) via processes such as, but not limited to: a) hydrothermal processing (for instance, by reacting the biomass on the order of 15 to 30 minutes in water at a very high temperature, typically 570° to 660° F. and pressure 100 to 170 atm standard atmosphere, enough to keep the water in a liquid state to form oils and residual solids); b) indirect liquefaction (for instance, a two-step process to produce ultra-low sulfur diesel by first converting the biomass to a syngas, a gaseous mixture rich in hydrogen and carbon monoxide, followed by catalytic conversion to liquids, the production of liquids is accomplished using Fischer-Tropsch (FT) synthesis as applied to coal, natural gas, and heavy oils; c) integrated catalytic thermochemical process such as integrated hydropyrolysis and hydroconversion (IH2); d) hydroprocessing (the hydrothermal liquefaction (HTL) of biomass provides a direct pathway for liquid biocrude production via two types of methods possible for conversion of fatty acids to renewable diesel: “high-pressure liquefaction” or “atmospheric pressure fast pyrolysis”).
Potable fresh water is produced as a byproduct of algal harvesting system 112 that can be recycled for other uses.
Turning now to
In this example, an algal core included a first algal growth component that was a heterotrophic component that included a heterotrophic algal strain and which generated and fed carbon dioxide to a second algal growth component was a photoautotrophic counterpart that included a photoautotrophic algal strain. It should be noted that the latter could be a photoautotrophic open pond/tank, or a hybrid system supporting photoautotrophic or mixotrophic growth.
Two sets of bioreactors were setup to represent a test (an embodiment of the algal core discussed above) and a control. The control system was a closed photobioreactor fed with ambient air. The test algal core included two closed reactors, a heterotrophic reactor and a photoautotrophic reactor (supporting heterotrophic and photoautotrophic algal growth, respectively), where the photobioreactor was connected to ambient air supply plus the additional carbon dioxide generated from the heterotrophic reactor produced as a result of a fermentation process. Both control and test systems were run in duplicate under the same temperature conditions, utilized artificially prepared media, and algae inoculums (also referred to as algae starter). In this experiment, when compared to the photoautotrophic counterpart, only half of the amount of algae starter was used in the heterotrophic reactor so as to maintain control over the heterotrophic reactor process.
For the heterotrophic reactor, additional glucose was added to the artificial media, and the reactor was run without exposure to light. The photobioreactors had the same, constant light supply in both the test and the control batches. All reactors were regularly monitored for optical density, which indicates algal density (process discussed and shown in
On the harvest day (day 7), the algal growth in the test algal core was found to be about 1.37 times higher (i.e., 37% more) than in the control reactor, which is considerable when extrapolated. For example, a typical, harvested photoautotrophic algae on dry weight basis is in the range of 300 mg/L (0.3 gm/L) to a 1 gm or more in photobioreactors. Using the more conservative harvest estimate, i.e., the 0.3 gm/L scenario, and extrapolating to an exemplary and typical 2000 ton/day algal growth system, a conventional photobioreactor system (or open pond system) would produce about 728,000 tons of algae biomass for oil extraction annually, whereas the photoautotrophic algal biomass harvest in the algal core, as discussed above, would be about 994,728 tons—a 266,728 ton surplus harvest.
As noted above, the heterotrophic reactor received 50% of the algae starter compared to the photobioreactor; however, if both reactors included an equal amount of algal inoculum, the amount of surplus algae from the heterotrophic reactor would be expected to double due to additional carbon dioxide generated by the heterotrophic reactor. If double the amount of heterotrophic algae was grown in the symbiotic system, this would contribute a surplus harvest of 3-4 times greater from the photobioreactor, thereby making the making the final surplus outcome about two or three times the harvest (i.e., about 74% to 111% more than the control). This example also illustrates how the volumes of the heterotrophic and photoautotrophic components in the symbiotic system could be customized to the algal harvest required from the two respective components. The surplus algal biomass generated could vary (lower or higher) in some embodiments depending on other factors such as media composition, light exposure, algae strain etc.
The examples and embodiments presented above could be applied to a variety of seed trains, where one system feeds a scaled-up version of the system. Various combinations of an SAS, such as SAS 100, could be made with the other existing algal growth systems and/or microbial growth systems.
SAS 100 can, in certain embodiments, include a Looped Algae Reactor Design Pattern (LARDP) 600, as shown in
LARDP 600 can include a series of nutrient extraction systems (NES) 604, such as first NES 604A and second NES 604B. Each NES 604 is designed to extract a certain type or types of components from an incoming effluent stream 608, such as an algal effluent stream from an algal growth component, such as AGC 152A or 152B, or from other sources described herein. In an exemplary embodiment, first NES 604A includes a first algal stage 612A that receives an effluent stream as an input. First algal stage 612A is sized and configured to use microorganisms, such as those previously described herein, to extract from effluent stream 608 a certain type or types of components, such as, but not limited to, a nitrogen, a phosphorus, a heavy metal, a toxic component, a particular element (e.g. Ca, K, Mg, Na, Al, Fe, Mn, B, Cu, Zn, S, Pb, Cd, As), a complex element such as an antioxidant (e.g. astaxanthin), and a nuclear component. First algal stage 612A allows for the growth of the microorganisms and, in certain embodiments, can be similar in design to AGC 152B. At a desired time, the algal biomass produced by first algal stage 612A is harvested at biomass processor 616A, which can be performed as described above. First algal stage 612A also produces an effluent 620, which is at least partially devoid of the component that first algal stage 612A was designed to remove. This effluent can proceed to one or more primary pathways. The effluent can 1) be recirculated back to first algal stage 612A for further extraction of components (not shown), 2) proceed to a water recycling unit 624 for further water treatment, 3) proceed to second algal stage NES 604B, and/or 6) return to algal culturing system 108 (
Second NES 604B and third NES 604C can be sized and configured to remove the same or a different type of component than that removed form first NES 604A. Second NES 604B thus can similarly include, a second algal stage 612B and a biomass processor 616B, and similarly third NES 604C can include, a third algal stage 612C and a biomass processor 616C. Additional stages 604 can be included to further extract components from effluent streams and recirculation to each stage in place in LARDP 600 can be performed. For example, if at first NES 604A, a first heavy metal is removed such that after entering the first NES it is present in the effluent stream in a lower concentration, the effluent can proceed to second NES 604B where another component, for example, a second heavy metal is removed to a lower concentration. The effluent from second NES 604B can then be recirculated to the first NES 604A for further removal of the first heavy metal, which is facilitated by the lower concentration of the second heavy metal.
In another exemplary embodiment, LARDP 600 is sized and configured to produce organic fertilizer from effluent steam 608. In this embodiment, at each NES 604 a desired fertilizer component is removed, e.g., nitrogen, phosphorus, potassium, etc. As each NES 604 allows for the harvesting of a concentrated amount of the desired component that is entrained within the organism, e.g., algae, in the NES, specific and fairly pure amounts of the component can be harvested and then mixed together to obtain the desired fertilizer product.
In use, when attached to an algal system, such as algal culturing system 108, microalgae disposed within LARDP 600 is cultivated in the effluent generated by the algae growth system. In this embodiment LARDP 600 is designed to remove undesirable substances such as, but not limited to, unwanted nutrients (e.g., nitrogen and phosphorus) and heavy metals. The biomass resulting from LARDP 600 can then be harvested from the wastewater and, depending on what LARDP has been designed to extract, processed to produce useful products such as, but not limited to, fertilizer and compost, or can be used as feedstock for digesters producing energy such as biogas or bio-electricity. After removal of the undesirable substances as described above, the remaining wastewater can then further be treated by cultering the same or a similar strain of microalgae as used in algal growth system 108 for producing the primary product, or the remaining waster can be further treated by one or more different algae strain(s) used as a monoculture or a polyculture with or without other microorganisms such as bacteria or fungi to further remove nutrients (e.g., nitrogen and phosphorus) or heavy metals or any other undesirable components present in the wastewater generated. LARDP 600 can be repeated in one or more stages with same or different strains of algae and/or bacteria and/or fungi or any other organisms compatible with algal strains, grown as a monoculture or polyculture in any type of algal growth system until the desired level of water quality is reached.
The number of NES 604s used in LARDP is determined by the number of desired removable elements in the effluent(s) that require capturing using microalgae or microbes and the desired water quality.
In an embodiment of the system, the one or more 604 stages in LARDP can be optionally combined or replaced by other processes such as multiple screening systems, decanting centrifugation, polymer flocculation, ammonia stripping, struvite formation, nitrification/de-nitrification, etc. Modifications of these processes can also be used for enhancing the whole process of nutrient removal.
LARDP 600 can be useful in the creation of products, including, but not limited, to biofuels, fertilizer, animal feed, and cosmetics. The organisms cultivated in LARDP 600 can be cultivated under a green house or other similarly enclosed environment, so as to prevent contamination by competitive microorganisms while admitting light. LARDP 600 can be implemented in, for example, vertical freestanding tanks, raceway style ponds, or tracks.
Additional useful byproducts from SAS 100 include the production of clean carbon dioxide (as compared to the CO2 captured from flue gases) generated from an algal growth component, such as AGC 152A, which, while discussed previously as supporting AGC 152B, can also be captured and used for other applications needing a clean source of CO2, e.g., medical applications, electronics, laboratories, etc. Alternatively, the CO2 can be used for algal inoculum-preparation (a highly concentrated algae culture typically used for seeding a larger scale system), especially to generate light-dependent inoculum for seeding a system or sub-system.
At step 708 it is determined whether any preprocessing is necessary prior to the stream entering the first NES. Preprocessing may be necessary if the stream contains significant solids or too much liquid. If preprocessing is necessary, process 700 proceeds to step 712 where a suitable preprocessing system is developed. Exemplary preprocessing systems are solids treatment unit 140 and separator 136 as discussed above with reference to
At step 716, a first NES is used to extract components from the waste or effluent stream. In an exemplary embodiment, first NES is sized and configured to focus on a relatively small number of components for extraction. For example, if the input waste or effluent stream is nitrogen rich, first NES may be configured to include an algal component that is primarily effective at removing a substantial portion of the nitrogen from the waste or effluent stream. The output of first NES is then provided to a second NES at step 720 for extraction of another component of the original waste or effluent stream.
At optional step 724, a determination is made as to whether further removal of nutrients from the output of step 720 is desired. As part of step 724 a determination of the composition of the output of step 720 may be completed so as to determine where, if anywhere, the output of step 720 should be sent. For example, in order to effectively remove a heavy metal from a waste stream, it is generally beneficial to remove nutrients that are in the stream in significant amounts. Therefore, if, for example, the output of step 720 included significant amounts of a nutrient, e.g., nitrogen, that would render extraction of the heavy metal difficult or inefficient, step 724 would determine that the stream should be sent to an NES that will efficiently remove more nitrogen (e.g., step 716). However, if removal of a different component is desired, process 700 may proceed to step 728 where a third NES is used to extract components form the output stream. If no further extractions are necessary, the process ends.
At step 808, the first algal strain is selected for algal growth component 152A. The selection is based on the composition of the input stream and the desired result from the growth of the algae, e.g., biomass production, reduction of an entrained element, heavy metal removal, etc. The growth characteristics of a given algal strain may be known from published research or may be understood through small-batch evaluation of algae that is bioprospected or genetically engineered.
At step 812, the composition of the effluent stream is evaluated so as to determine the components in the stream.
At step 816, a determination is made as to whether the effluent stream needs to be supplemented with additional nutrients to promote growth. For example, in the brewery waste example above, the effluent was low in organic carbon. If the system designer desires to use an algal strain that needs some organic carbon for growth, a supplemental source may be provided at step 820.
If no supplement is needed or if the supplement has been provided, the process proceeds to step 824 where a decision is made as to whether to treat the effluent stream. The effluent stream may need treatment depending on its contents, the desired output of the entire system, and the desired algal strain that is used in algal growth component 152B. For example, if the effluent includes a growth inhibiting component, and, while a suitable algal strain can be used, another strain would produce a more desirable outcome but would be partially inhibited by the contents of the effluent, the effluent can be treated. In a preferred embodiment, the selection of the first and second algal strains for AGC 152A and 152B, respectively, are chosen so as to not inhibit the growth of either strain so as to avoid system complexity.
If it is desired to treat the effluent stream, the process proceeds to step 828. If no treatment is desired, the process proceeds to step 832.
As is evident, many of the steps of process 800 are dependent on other steps as well as the desires of the system designer.
Turning now to a discussion of
As shown in
In an exemplary aspect, a symbiotic algae system is disclosed that comprises: a first algal growth component, wherein the first algal growth component includes a heterotrophic organism, and wherein the first algal growth component produces a first effluent and an off-gas; and a second algal growth component is fluidly coupled to the first algal growth component, and the second algal growth component including at least one organism from the group of: a photoautotrophic organism, a mixotrophic organism, and a heterotrophic organism, and wherein the second algal growth component receives, as an input, the first effluent and the off-gas and produces a second effluent. In the symbiotic algae system, the first algal growth component can receive, as a first input, an effluent input or a waste input. In the symbiotic algae system, the second algal growth component can receive, as a second input, an effluent input or a waste input. The symbiotic algae system can further include a waste nutrient preparation sub-system fluidly coupled to the first algal growth component. In the symbiotic algae system, the waste nutrient preparation sub-system can receive an effluent input, a fresh water input, and waste input, and outputs an effluent suitable for use by the first algal growth component. In the symbiotic algae system, the waste nutrient preparation sub-system is a manure settling and solids preparation unit that outputs liquid manure waste to the first algal growth component. The symbiotic algae system can further include an algal harvesting system having at least one separator, wherein the algal harvesting system is fluidly coupled to the first algal growth component and/or the second algal growth component. The symbiotic algae system can have an EROI greater than 10. The symbiotic algae system can have an EROI of about 40. The symbiotic algae system can further comprise a third algal growth component, wherein the third algal growth component includes at least one organism from the group of: a photoautotrophic organism, a mixotrophic organism, and a heterotrophic organism, and wherein the third algal growth component receives, as an input, the second effluent. The symbiotic algae system can further comprise at least one biomass processing system, the biomass processing system sized and configured to extract lipids from at least one of the first algal growth component and the second algal growth component.
In another exemplary aspect, a symbiotic algae system is disclosed that comprises a first algal growth component, wherein the first algal growth component includes a heterotrophic organism, and wherein the first algal growth component produces a first effluent and an off-gas; and a second algal growth component fluidly coupled to the first algal growth component, wherein the second algal growth component includes at least one organism from the group of: a photoautotrophic organism, a mixotrophic organism, and a heterotrophic organism, and wherein the second algal growth component receives, as a first input, the first effluent and the first off-gas and produces a second effluent and a second off-gas; and wherein the second effluent and the second off-gas are received as inputs to the first algal growth component. In the symbiotic algae system, the first algal growth component can receive, as an additional input, an effluent input or a waste input, and wherein the additional input and the second effluent include a nitrogen and a phosphorous. In the symbiotic algae system, the first algal component can remove a portion of the nitrogen and the phosphorus from the second input and the additional input. The symbiotic algae system can further comprise a third algal growth component, wherein the third algal growth component includes at least one organism from the group of: a photoautotrophic organism, a mixotrophic organism, and a heterotrophic organism, and wherein the third algal growth component receives a portion of the second effluent. The symbiotic algae system can further comprise at least one biomass processing system, the biomass processing system sized and configured to extract lipid/oil from at least one of the first algal growth component and the second algal growth component. The symbiotic algae system can have an EROI greater than 10. The symbiotic algae system can have an EROI of about 40.
In yet another exemplary aspect, a symbiotic algae system can comprise: a waste nutrient preparation sub-system; an algal culturing system including: a first algal growth component fluidly coupled to said waste-nutrient preparation sub-system, wherein the first algal growth component includes a heterotrophic organism, and wherein the first algal growth component produces a first effluent and an off-gas; and a second algal growth component, wherein the second algal growth component includes at least one organism from the group of: a photoautotrophic organism, a mixotrophic organism, and a heterotrophic organism, and wherein the second algal growth component receives, as an input, the effluent and the off-gas and produces a second effluent; and an algal harvesting system fluidly coupled to said algal culturing system; an algal biomass processing system fluidly coupled to said algal harvesting system; and a byproducts system fluidly coupled to said algal biomass processing system. In the symbiotic algae system, the waste nutrient preparation sub-system can receive, as an input, an effluent input or a waste input.
In an embodiment, a symbiotic algae system for removing nutrients from an input stream including organic carbon waste matter that is either phosphorus rich or nitrogen rich, the symbiotic algae system comprises a first algal growth component, wherein the first algal growth component includes a first container suitable for growing a first heterotrophic algae strain, and wherein the first algal growth component produces a first algal biomass, a first effluent including a portion of the organic carbon waste matter and a first growth byproduct, and a carbon dioxide rich off-gas; and a second algal growth component fluidly coupled to the first algal growth component, the second algal growth component including a second container suitable for growing a second algal strain, wherein the second algal strain is a different strain than the first heterotrophic algae strain, and wherein the second algal growth component produces a second algal biomass, a second effluent including a smaller portion of the organic carbon waste matter and a second growth byproduct, and an oxygen rich off-gas, a first algal harvesting system coupled to the first container and a second algal harvesting system coupled to the second container, wherein the first algal harvesting system separates the first algal biomass from the first effluent and the second algal harvesting system separates the second algal biomass from the second effluent, and wherein the second algal growth component receives, as an input, the first effluent, after removal of the first algal biomass, and the carbon dioxide rich off-gas, and wherein the first algal growth component receives the second effluent, after removal of the second algal biomass, and the oxygen rich off-gas, and wherein the first heterotrophic algae strain is selected based upon the input stream, and wherein the second algal strain is selected based upon the first effluent. Additionally or alternatively, wherein the first algal growth component does not receive any oxygen from any other source besides second algal growth component. Additionally or alternatively, wherein the second algal growth component does not receive any carbon dioxide from any other source besides first algal growth component. Additionally or alternatively, wherein the second algal growth component receives, as a second input, a waste input, and wherein the algal strain is selected based upon the first effluent and the waste input. Additionally or alternatively, wherein the first algal biomass is not harvested until the first heterotrophic algal strain is mature. Additionally or alternatively, wherein the system has an EROI greater than 10. Additionally or alternatively, wherein the system has an EROI of about 40. Additionally or alternatively, wherein the symbiotic algae system further comprises at least one biomass processing system coupled to the first and/or second algal harvesting system, the biomass processing system sized and configured to extract one or more of a lipid, a protein, a carbohydrate, a metabolite, and a dye, from the first algal biomass and/or the second algal biomass.
In another embodiment, a symbiotic algae system for removing nutrients from an input stream including organic carbon waste matter that is either phosphorus rich or nitrogen rich, the symbiotic algae system comprises a first algal growth component, wherein the first algal growth component includes a first container suitable for growing a first heterotrophic algae strain, and wherein the first algal growth component produces a first algal biomass, a first effluent including a portion of the organic carbon waste matter and a first growth byproduct, and a carbon dioxide rich off-gas; and a second algal growth component fluidly coupled to the first algal growth component, the second algal growth component including a second container suitable for growing a second algal strain, wherein the second algal strain is a different strain than the first heterotrophic algae strain, and wherein the second algal growth component produces a second algal biomass, a second effluent including a smaller portion of the organic carbon waste matter and a second growth byproduct, and an oxygen rich off-gas, and wherein the second algal growth system receives, as an input, the first effluent and the carbon dioxide rich off-gas wherein the first algal growth system receives the second effluent, and wherein the first heterotrophic algae strain is selected based upon the input stream and the second effluent, and wherein the second algal strain is selected based upon the first effluent. Additionally or alternatively, wherein the first algal strain also receives the oxygen rich off-gas. Additionally or alternatively, wherein the first algal growth component does not receive any oxygen from any other source besides second algal growth component. Additionally or alternatively, wherein the second algal growth component does not receive any carbon dioxide from any other source besides first algal growth component. Additionally or alternatively, wherein the symbiotic algae system further includes a first algal harvesting system coupled to the first container and a second algal harvesting system coupled to the second container, wherein the first algal harvesting system separates the first algal biomass from the first effluent and the second algal harvesting system separates the second algal biomass from the second effluent. Additionally or alternatively, wherein the symbiotic algae system further comprises at least one biomass processing system coupled to the first and/or second algal harvesting component, the biomass processing system sized and configured to extract lipids from the first algal biomass and/or the second algal biomass. Additionally or alternatively, wherein the second effluent is not further treated or processed prior to delivery to first algal growth component. Additionally or alternatively, wherein the second algal growth component receives, as a second input, a waste input, and wherein the algal strain is selected based upon the first effluent and the waste input. Additionally or alternatively, wherein the first algal biomass is not harvested until the first heterotrophic algal strain is mature. Additionally or alternatively, wherein the system has an EROI greater than 10.
A symbiotic algae system according to claim 9, wherein the system has an EROI of about 40.
Exemplary embodiments have been disclosed above and illustrated in the accompanying drawings. It will be understood by those skilled in the art that various changes, omissions and additions may be made to that which is specifically disclosed herein without departing from the spirit and scope of the present invention.
This application is a continuation-in-part application of U.S. patent application Ser. No. 15/856,805, filed Dec. 28, 2017, entitled “Symbiotic Algae System,” which is a divisional of U.S. patent application Ser. No. 14/932,218, filed Nov. 4, 2015, and entitled “Symbiotic Algae System”, which is a continuation-in-part of U.S. patent application Ser. No. 14/888,986, filed Nov. 4, 2015, entitled “Symbiotic Algae System with Looped Reactor,”, which is a national stage entry of PCT Application No. PCT/US15/56344, filed on Oct. 20, 2015, and entitled “Symbiotic Algae System with Looped Reactor,” which claims priority to U.S. provisional application Ser. No. 62/067,049, filed Oct. 22, 2014, and entitled “Symbiotic Algae System with Looped Reactor,” U.S. provisional application Ser. No. 62/067,042, filed Oct. 22, 2014, and entitled “Symbiotic Algae System,” and U.S. provisional application Ser. No. 62/079,135, filed Nov. 13, 2014, and entitled “Algal Growth System Process Utilizing Intermediate Products of Consolidated Bioprocessing Process or Anaerobic Digestion Process,” each of the aforementioned applications are hereby incorporated by reference herein in their entirety. This application is also a continuation-in-part of PCT Application No. PCT/US2018/067972, filed Dec. 28, 2018 and entitled “Systems and Methods of Producing Compositions from the Nutrients Recovered from Waste Streams,” which claims priority to U.S. patent application Ser. No. 15/856,642, filed Dec. 28, 2017 and entitled “Systems and Methods of Producing Compositions from the Nutrients Recovered from Waste Streams,” each of the aforementioned applications are hereby incorporated by reference herein in their entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62067049 | Oct 2014 | US | |
| 62067042 | Oct 2014 | US | |
| 62079135 | Nov 2014 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 14932218 | Nov 2015 | US |
| Child | 15856805 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15856642 | Dec 2017 | US |
| Child | PCT/US18/67972 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15856805 | Dec 2017 | US |
| Child | 16387163 | US | |
| Parent | 14888986 | Nov 2015 | US |
| Child | 14932218 | US | |
| Parent | PCT/US18/67972 | Dec 2018 | US |
| Child | 14888986 | US |
